Patent Application
20110148661
The present invention relates to a guiding device that adequately guides a mobile body such as a human, a vehicle, and an airplane.
Road display devices are needed that allow, for example, a driver to drive safely a vehicle such as an automobile in the nighttime or in dark locations, or to park the vehicle safely in a parking lot in a dark sites.
A “Self-Emitting Road Rivet” that enables a vehicle driver to see clearly a horizontal light-emitting surface from a distance and also to enable an approaching vehicle driver or pedestrian to see clearly an upward light-emitting surface has been suggested as such a road display device (see, for example, Patent Document 1). Such a road display device is provided with an accommodation portion in an adequate installation side on a road, a light-emitting diode is disposed in the accommodation portion, the light emitted from the light-emitting diode is guided on the ground by fibers and the arrangement method and cut specifications of the fibers make it possible to obtain the road display device with good visibility.
Further, it has also been suggested to use such fibers and laser to perform road display in heavy-snow regions (see, for example, Patent Document 2). With such a road display device, by using the linearity of the laser beam emitted from a laser, it is possible to recognize the display contents of the road display through snow or rain even in the zones with snow accumulation.
Block products for roads have also been suggested that have self-emitting devices embedded and integrated therewith and facilitate recognition and guidance for vehicles and people in the nighttime by disposing fiber cables (see, for example, Patent Document 3). A variety of display methods can be used with such road display devices, and all-weather solar power sources have been used therewith. As a result, the power source can be repeatedly charged and discharged regardless of the installation site and a maintenance-free product with a long service life is obtained.
However, the above-described configurations of the conventional road display devices require a light source to be disposed close to the irradiation site. As a result, when the laser source is used outdoors, high-level waterproofing is required. In particular, when long-distance irradiation is performed, cost is increased. Another problem is that when the laser light source should be replaced, for example, at the end of service life thereof, large-scale road work is required, and the work takes a long time and requires a high cost.
Patent Document 1: Japanese Laid-Open Patent Publication No. 7-305313
Patent Document 2: Japanese Laid-Open Patent Publication No. 2002-38433
Patent Document 3: Japanese Utility Model Registration No. 3036936
It is an object of the present invention to provide a guiding device that excels in visibility, while being simple in construction and installation at a low cost.
A guiding device according to one aspect of the present invention guides a mobile body by light and includes a laser light source that emits a laser beam, and a linear guiding portion that propagates the laser beam and is extended in a guiding direction on a road surface on which the mobile body travels, wherein the linear guiding portion irradiates the laser beam with directivity in the guiding direction from a surface where the linear guiding portion extends, while propagating the laser beam.
With the above-described configuration, by extending the linear guiding portion connected to the laser light source, it is possible to guide by light easily and within a wide range. As a result, it is possible to realize a low-cost guiding device that is simple in structure and installation and easy to maintain. Further, the guiding device can irradiate a laser beam with good directivity along the guiding direction. As a result, it is possible to realize a guiding device of excellent visibility that can be easily seen by a driver of a mobile body.
Other objects, features, and advantages of the present invention can be fully understood from the description presented below. The merits of the invention will be apparent from the following explanation given with reference to the appended drawings.
The embodiments of the preset invention will be described below with reference to the appended drawings. Like elements are assigned with like reference numerals and explanation thereof may be omitted. The drawings schematically illustrate the constituent elements for the sake of convenience of explanation and do not always accurately represent the shape thereof.
An embodiment of the present invention will be described below with reference to
As shown in
The laser light source 14 of the present embodiment is adequately disposed inside an administrative building 16 located outside the runway (road surface) 11.
The operation temperature of laser light sources and drive circuits is generally preferred to be maintained at a normal temperature level to extend the service life thereof. Accordingly, in the present embodiment, the laser light source 14 is disposed indoors in order to prevent the laser light source from operating under a high temperature environment even in a blazing summer heat. Further, in this case, the laser light source 14 can be adequately protected from water, atmosphere, and sunlight. As a result, the service life of the laser light source 14 can be extended and therefore the service life of the entire guiding device 10 can be extended.
The present embodiment is not limited to the above-described configuration and it is also possible, for example, to provide an adequate storage chamber below the runway 11 and dispose the laser light source 14 inside the storage chamber. As a result, the laser light source 14 can be adequately protected from water, atmosphere, and sunlight in the same manner as when it is disposed in the room of the administrative building 16.
Even when it is necessary to replace the laser light source 14 because of the end of the service life thereof, the fiber 15a that is a light guiding portion is not necessary to replace, and only the laser light source 14 located inside the administrative building 16 can be replaced. Therefore, the laser light source 14 can be replaced, regardless of the presence of the airplane 12 on the runway 11 and therefore the convenience can be increased. In addition, since the replacement is done in one location, the number of operations required for the replacement can be reduced. It goes without saying that the installation location of the laser light source 14 is not limited to that inside the administrative building or storage chamber, provided that the laser light source is not exposed to high temperature and can be easily replaced.
Because of the object of use thereof, the linear guiding portion 15 is disposed outdoors and connected to the laser light source 14 located inside the administrative building 16. In the linear guiding portion 15, the laser beam 13 emitted from the laser light source 14 propagates inside the fiber 15a. The fiber 15a constituting the linear guiding portion 15 is composed of electrically insulating quarts glass or resin and is highly flexible. Therefore, the linear guide portion 15 can be disposed in the desired location both longitudinally and transversely along the runway 11 of the airport, for example, as shown in
In the guiding device 10 of the present embodiment, the laser light source 14 is disposed, as described hereinabove, in an adequate position inside a room of the administrative building 16 in order to avoid the exposure to water, atmosphere, and sunlight. Therefore, the guiding device 10 can be operated with good stability for a long time.
A fiber 15b shown in
A fiber 15a shown in
Thus, a linear guiding portion can be easily realized by using a fiber including the diffusing material 15d in either the cladding 15e or the core 15c. Further, with such a configuration, the desired laser beam 13 can be easily irradiated with good directivity by appropriately designing the arrangement or density of the diffusing material 15d inside the fiber 15.
The linear guiding portion 15 of the present embodiment illustrated by
The fiber of the present embodiment is preferably configured to have a coating on the propagation portion A and include no diffusion material 15d inside the propagation portion A, as in the fiber 15f shown in
The entire portion of the fiber disposed along the runway 11 may be the irradiation portion B, or only part thereof may be the irradiation portion B, as shown in
In the case of a fiber in which the above-described irradiation portions B and propagation portions A are formed repeatedly with a short period, uniformly bright irradiation can be ensured over the entire region of the fiber by increasing the ratio of the irradiation portions B in the downstream direction. Thus, the quantity of light in the laser beam propagating inside the fiber decreases in the downstream direction. In this case, by increasing the ratio of the irradiation portions B inside the fiber, as described hereinabove, it is possible to compensate the brightness of the emitted laser beams, thereby enabling uniformly bright irradiation. Where the entire region inside the fiber is the irradiation portion B, it is desirable that the amount of the diffusing material 15d per unit length be increased in the downstream direction of the fiber. With such a configuration, by increasing the amount of the diffusing material 15d per unit length in the downstream direction in which the quantity of light in the laser beam decreases, it is possible to increase the quantity of light in the laser beam that is taken out, thereby enabling uniformly bright irradiation over the entire region of the fiber, in the same manner as in the above-described configuration.
Further, in the configuration shown in
As shown in
With the above-described configuration, laser beams 13 with rich color and excellent color reproducibility can be emitted and therefore visibility of the guiding device 10 can be further improved.
Further, when a laser light source including no RGB beam source is used as the laser light source 14 constituting the linear guiding portion 15, it is preferred that a beam source including at least the G beam source 14G be used. In this case, it is preferred that a high-output SHG laser excited by a semiconductor laser and emitting the G beam 13G with a wavelength close to 535 nm be used. With such a configuration, the green laser beam 13 with high visibility to human eyes can be used and therefore visibility can be increased with good efficiency at a low power consumption level.
The laser beams 13 emitted from the laser light source 14 shown in
In this case, when a single-mode laser is used as the laser light source 14, it is possible to use fluctuations of the laser beam 13 outgoing from the linear guiding portion 15 to the outside, those fluctuations being caused by spectral noise. Thus, spectral noise causes the laser beam 13 to fluctuate in time and space and therefore, the vicinity of the laser beam 13 from the linear guiding portion 15 can be further increased.
Further, the above-described configuration makes it possible to realize a guiding device 10 that is simple in structure and installation and easy to maintain and excels in visibility.
As shown in
With such a configuration, the laser beam 13b can be easily emitted with even better directivity. The configuration shown in
The configuration shown in
An end surface of the fiber 30 of the above-described configuration on the side opposite that of the light incidence side is connected to a pump 34. The pump 34 accommodates inside thereof the liquid 32 and the liquid 33 including the diffusing material 35 and is configured such that the liquid 32 and the liquid 33 including the diffusing material 35 can be alternately jetted out into the cladding 31 under the control performed by a control unit 36. As a result, the liquid 33 including the diffusing material 35 can be disposed in any position inside the fiber 30, as shown in
When the refractive index of the liquid 32 and liquid 33 is higher than the refractive index of the cladding 31, the laser beam 13 that has entered the liquid 32 or the liquid 33 propagates, while undergoing total reflection at a boundary surface of the cladding 31 and the liquid 32 and at a boundary surface of the cladding 31 and the liquid 33, in the same manner as is usually observed in quartz fibers. In this case, where the incoming laser beam 13 reaches the liquid 33, the laser beam is diffused by the diffusing material 35 located inside the liquid 33 and exits the fiber 30. The quantity of light exiting from each position of the fiber 30 can be set to a random value by adjusting the density of the diffusing material 35 in the same manner as in the case of the fiber 15f shown in
Further, by actuating the pump 34 after the laser beam 13 has entered the fiber 30, it is possible to perform the adjustment by moving the liquid 32 and the liquid 33 inside the fiber 30. As a result, the irradiation position can be adjusted to a desirable position.
In another possible configuration, three fibers of the above-described configuration are bundled together, red, blue, and green laser beams are introduced into the fibers by one color per fiber, and the colors of the fibers are combined together. As a result, any position can be irradiated with any color.
When the refractive index of the liquid 32 or the liquid 33 serving as a core is less than the refractive index of the cladding 31, the laser beam 13 that has entered the fiber 30 propagates inside the fiber 30, while undergoing total reflection at a boundary of the cladding 31 and the atmosphere, rather than on the boundary of the cladding 31 and the liquid 32 or the liquid 33. In this case, even when the position of the liquid 33 is reached inside the fiber 30, the light present inside the cladding 31 at this time passes through without diffusion.
Accordingly, it is preferred that the cross-sectional area of the cladding 31 is larger than that of the core in the location into which the liquid 32 and the liquid 33 have been injected. In this case, since the laser beam can be caused to propagate a long distance in the fiber 30, such a configuration is effective when gradual diffusion over a long distance is desired. In the present embodiment, a configuration using two kinds of liquids, namely, the liquid 32 and the liquid 33, is described, but such a configuration is no limiting. Thus, it goes without saying that three or more kinds of liquids may be used or the diffusing material 35 may be introduced in the liquid of one kind. When the diffusing material 35 is introduced in the liquid of one kind, the effect similar to that obtained with the fiber 15a shown in
The kinds of the liquid 32 and the liquid 33 are not limited to the above-described examples, provided that the liquids are transparent and mutually insoluble.
Generally a laser beam enters the tapered fiber 40 from a thin side and exits from a thick side, so that the outgoing laser beam is close to a substantially parallel beam. However, in the configuration shown in
As shown in
The tapered fiber 40 shown in
In the tapered fiber 40, the refractive index of the cladding is usually made lower than that of the core, whereby total reflection is induced at the end surfaces of the core and the cladding and the light is caused to propagate a long distance. However, when the light is taken out of the tapered fiber 40 as in the present embodiment, the light can be easily taken out of the tapered fiber 40 over a long region with a uniform distribution by increasing the refractive index of the cladding over that of the core.
For example, when light enters a substance with a high refractive index (for example, acrylic resin or the like: refractive index 1.5) from a substance with a low refractive index (for example, air: refractive index 1.0), the transmissivity of light (average for S and P polarized light) changes from 0 to 90% for example within a very narrow range (5°) of the angle of incidence of 42° to 37° (see (1) in
However, when the incidence direction is reversed and the laser beam enters a substance with a low refractive index (for example, air: refractive index 1.0) from a substance with a high refractive index (for example, acrylic resin or the like: refractive index 1.5), the range of the angle of incidence in which the transmissivity of light (average for S and P polarized light) changes from 0 to 90% is greatly widened to about 30° (see (2) in
For example, when a beam having a Gaussian distribution with a beam radius of 400 μm (1/ê2) and a spread angle of 0.5° (half-width: 1/ê2) enters a tapered fiber with taper angle θ of 0.02°, a core radius at a thick side of 500 μm, a length of 1 m, a refractive index of 1.44 of the core, and a refractive index of 1.49 of the cladding including a diffusing material, the light can propagate with a spread in luminance within a range of 20% over the region covering almost the entire length of the fiber.
When a beam having a Gaussian distribution with a beam radius of 400 μm (1/ê2) and a spread angle of 0.9° (half-width: 1/ê2) enters the same fiber having a refractive index of 1.0 (that is, hollow) of the core, the light can propagate with a spread in luminance within a range of 20% over the region covering almost the entire length of the fiber. It goes without saying that a variety of combinations can be set correspondingly to the desired irradiation length or properties (refractive index, core diameter, and the like) of the fiber used.
In the above-described example, a case is explained in which the refractive index of the core in the tapered fiber is lower than the refractive index of the cladding. However, even in the usual fiber that has not been tapered, where the refractive index of the cladding is made higher than that of the core, although the angle of incidence on the fiber end surface is not changed, the effect of gradually taking the light to the outside of the fiber is clearly demonstrated, as in the tapered fiber. Therefore, the laser beam can be irradiated over a long region even in the case of the usual fiber that has not been tapered.
Further, it is preferred that the taper angle θ vary depending on the location in the tapered fiber 40. In this case, the quantity of outgoing light in any location can be adjusted. Thus, by increasing the taper angle θ in a location with a low luminance, it is possible to increase the intensity of the laser beam exiting the fiber from this position and a more uniform laser beam can be obtained.
Similarly to the configuration shown in
The laser beam 13 that has entered the fiber 41 and exited from the fiber 41 enters the tapered fiber 40. The laser beam 13 that has entered the tapered fiber 40 is little by little taken to the outside of the tapered fiber 40, as shown in
Furthermore, even when no taper is formed in the tapered fiber 40, the laser beam can circulate, while being scattered at a very low rate, in the loop constituted by the tapered fiber 40 and the fiber 42. As a result, uniform irradiation from the tapered fiber 40 and the fiber 42 can be obtained.
As shown in
In this case, since plane-like irradiation of the laser beam 13b can be obtained, the laser beam can be irradiated such that has a certain width on the runway 11. As a result, further improvement in visibility can be realized.
With the configuration such as shown in
A light-guiding sheet 60 shown in
Where the light-guiding sheet 60 is connected to the fiber 55 and the laser beam 13 enters the light-guiding sheet 60 from the fiber 55 in this state, the laser beam 13 propagates inside the light-guiding sheet 60. Part of the laser beam 13 can be irradiated with good directivity as a laser beam 13b from cross sections 62 facing upward in the vicinity of the apertures 61 produced by pulling the light-guiding sheet 60 in the direction of arrow (1).
Further, by changing the intensity of pulling in the direction of arrow (1), it is possible to change the orientation of the outgoing laser beam 13b. In the case of installation on a road surface, as in the present embodiment, for example, where the fibers 55 have a mesh-like arrangement and used as a linear guiding portion, when a mobile body passes above the fibers, the fibers can be cut. In such a case, in the fibers that have been cut, no laser beam can be irradiated as a linear guiding portion downstream of the cutting position.
Accordingly, where the above-described light-guiding sheet 60 is used, even if part of the propagation path is cut, the laser beam from other locations still propagates and therefore, the laser beam can be irradiated even downstream of the cutting position of the propagation path. As a result, a laser beam can be irradiated with good directivity within a wide range by using a simple configuration, and a highly reliable guiding device can be realized.
In the above-described configuration, it is preferred that the light-guiding sheet 60 be provided with a reflective film made from a metal or the like on the upper surface and lower surface before the light-guiding sheet 60 is stretched. As a result, the light can be more reliably confined within the light-guiding sheet 60 and therefore a fiber can be configured that ensures efficient and low-loss propagation.
With the above-described configuration, it is possible to realized a guiding device 10 that is simple in structure and installation and easy to maintain and excels in visibility.
The configuration shown in
The above-described configuration is not limiting provided that the prism sheet 51b shown in
Another embodiment of the present invention will be described below with reference to
A guiding device 100 shown in
As shown in
When the automobile 102 is parked by backing up in the direction of an arrow 102a along the road surface 101 of the parking area till the wheel stoppers 105 are reached, the laser beam 13 is irradiated from the fibers 103 of the linear guiding portion 104. The laser beam 13 is thus irradiated with good directivity along the direction indicated by the arrow 102a. As a result, the driver of the automobile 102 can recognize with good visibility the position and direction of the linear guiding portion 104 in the parking area.
The laser light source 14 and a power source 14c for driving the laser light source are disposed in a control box 106. The control box 106 is provided outside the road surface 101 adjacently to the parking area or below the road surface 101 and disposed to be shielded from atmosphere or rain. Further, the fiber 103 constituting the linear guiding portion 104 and the fiber 103a that is connected to the laser light source 14 are buried below the road surface 101 as shown in
When the automobile 102 is driven in the direction of an arrow 102b to exit from the parking area, the laser beam 13 is irradiated with good visibility for the driver along the direction indicated by the arrow 102a. As a result, the driver can recognize with good visibility the position and direction of the linear guiding portion 104 of the parking area and can safely drive the automobile out of the parking area.
With such a configuration, similarly to the above-described configuration, it is possible to realize the guiding device 100 that is simple in structure and installation and easy to maintain and excels in visibility. Further, with the present guiding device 100, since the laser beam 13 is irradiated with good visibility along the road surface 101, the laser beam can be easily seen by the driver of the automobile 102 and excellent visibility is attained. In addition, the laser light source 14 can be adequately protected from water, atmosphere, and sunlight and the service life of the device can be extended.
Further, for example, by attaching sensors to the wall surface, measuring the distance from the automobile 102 to the wall surface and automatically changing the color of the laser beam 13 correspondingly to the distance from the automobile 102 to the wall surface it is possible to warn the driver of the automobile 102 coming too close to the wall surface when the automobile is parked or driven out of the parking area, thereby ensuring safe driving.
For example, when the configuration of the fiber 15a shown in
The linear guiding portion 110 can be easily realized by using such a fiber including a diffusing material in at least either of the core and cladding. Further, with such a configuration, by adequately designing the arrangement or density of the diffusing material inside the fiber, it is possible to irradiate the laser beam 13 easily with good directivity along the direction of an arrow 102c in which an automobile 102 is driven. As a result, the driver of the automobile 102 can recognize the linear guiding portion 107 as a lane line with good visibility even in the nighttime and safe driving can be ensured. On highways and general roads where passing is allowed, the center line is shown by a broken line (on highways, a white line with a length of 8 m and a spacing of 12 m; on a general road, a white line with a length and spacing of 5 m).
Therefore, the fiber of the above-described embodiment can be used in the below-described manner.
Thus, when the configuration of the fiber 15f shown in
Likewise, when the configuration of the fiber 17 shown in
In the configuration shown in
In the example shown in
The entry direction of the laser beam 13 to the fiber is preferably selected such that the laser beam 13 going out of the fiber is irradiated forward of the automobile 102. In this case the laser beam 13 can be irradiated even more easily with good directivity with respect to the driver of the automobile 102 driven in the direction of arrow 102d. As a result, the driver of the automobile 102 can recognize the linear guiding portion 110 as a line of a curved lane with good visibility even in the nighttime, and the driver can safely drive the automobile 102.
In this case, the laser beam 13 can be irradiated even easier with good directivity. Therefore, the driver of the automobile 102 can recognize the linear guiding portion 110 as a lane line inside the tunnel with good visibility despite the fact that it is darker inside the tunnel than outside. As a result, the driver can safely drive the automobile 102 even in a dark tunnel. It goes without saying that other fibers (20, 30, 40, and the like) can be used for the linear guiding portion 110 shown in
A configuration including the propagation portions A in which the laser beam 13 from the laser light source 14 propagates with low loss and the irradiation portions B that irradiate the laser beam 13 with good directivity by diffusion may be applied to the linear guiding portions 104 and 110 shown in
A guided device 130 shown in
The operation of the linear guiding portion 121 will be described below. The laser beam 13 entering the fiber 122 propagates in the fiber 122 and arrives directly below a contact portion 123a. The refractive index of the contact portion 123a is set slightly higher than that of the fiber 122. Part of the laser beam 13 enters from the fiber 122 to the contact portion 123a, and the remaining laser beam 13 continues propagating inside the fiber 122. When the contact portion 123a includes a diffusing material inside thereof, the laser beam that has entered the contact portion 123a is scattered forward. Even with a configuration that uses no diffusing material, for example, if a prism sheet is used as explained in Embodiment 1 with reference to
The contact portion 123b of the present embodiment is normally not in contact with the fiber 122. However, for example, when the environment gets darker, the contact portion can be lowered and brought into contact with the fiber 122, if necessary, thereby making it possible to emit the laser beam 13b from the contact portion 123b in the same manner as in the case of the above-described contact portion 123a. Since the density of the location irradiated correspondingly to the lightness of the environment can be adjusted, the driver of the automobile 102 can recognize the linear guiding portion 121 along the road surface 101 with good visibility even in the nighttime. As a result, the driver can safely drive the automobile.
The guiding device shown in
When the laser beam 13 that has entered the fiber 132 arrives directly below the contact portion 123a, part of the light enters the contact portion 123a and exits as a laser beam 13b to the outside.
In the linear guiding portion 131, the quantity of light of the laser beam 13 exiting from the extension surface of the laser light source 14 decreases with the distance from the laser light source, but in the linear guiding portion 132 that has been folded back and arranged in parallel rows as described hereinabove, the sites with a large distance and sites with a small distance from the laser light source 14 are parallel to each other and overlap each other, a substantially uniform irradiation intensity of the laser beam from each position along the road surface can be obtained, and visibility can be increased.
The laser beam 13 remaining inside the fiber 132 reaches the other contact portion 123a and is similarly taken out to the outside of the contact portion 132a. In this case, the fiber 132 is folded back when installed in the guiding device 130. Therefore, the laser beam 13 enters the same contact portion 123a again from the direction opposite the entrance direction into the contact portion 123a. Since the quantity of light in the laser beam 13 propagating inside the fiber 132 decreases each time the fiber 132 comes into contact with the contact portion 123a, the quantity of light emitted from the contact portion 123 upstream of the fiber 132 is larger than the quantity of light emitted from the contact portion 123 on the downstream side. In the guiding device 130, the installed fiber 132 is folded back. As a result, each contact portion comes twice into contact with fiber 132. As for the quantity of light exiting each contact portion, a substantially identical total quantity of light (before the folding and after the folding) can be caused to exit, regardless of the position of the contact portions 123 on the fiber 132. Further, the laser beam 13 from the fiber 132 enters the contact portion 123 from both sides, that is, from the left side and from the right side, as shown in
The operation of the contact portion 123b in a state without contact with the fiber 132 (usual state) is similar to that in the aforementioned guiding device 120 shown in
With the configuration shown in
A guiding device according to yet another embodiment of the present invention will be described below with reference to
As shown in
In this configuration, as shown in
The fibers 142a and 142b may have a configuration including a diffusing material 15d, for example, as in the fibers 15a, 15b, and 15f shown in
The linear guiding portion 141 of the present embodiment has a function of guiding the automobile (mobile body) 102 by irradiating the laser beam 13 with good directivity in the direction along the road surface 101. Further, where the laser bean 13 enters the fiber from the front side of the automobile 102, the laser beam can be irradiated from the front side of the automobile 102, while the fiber remains disposed parallel to the road, as shown in
The above-described configuration makes it possible to realize the guiding device 140 that is simple in structure and installation and easy to maintain and excels in visibility. Further, with the guiding device 140, the laser beam 13 can be irradiated with good directivity along the road surface 101. Therefore, a linear guiding portion of excellent visibility that can be easily seen by the driver of the automobile 102 can be realized.
As shown in
Further, as shown in
In this case, viewable information such as traffic information can be provided to the driver under various circumstances by switching on the laser beam 13 at a speed that can be visually recognized by a person, in addition to the guiding function. When the laser beam 13 is modulated at a frequency equal to or below 0.1 Hz or above 10 Hz, the level recognizable by human eye is exceeded and the modulation rate is too high.
In another possible configuration that provides traffic information to the driver of the automobile 102, color of the laser beam 13 is changed, instead of modulating the laser beam 13. For example, when there is highway traffic jam information and the distance from the present location to the jam zone and the length of the jam zone are represented by switch-on frequency and color (when there is no jam, the color is green and the color changes from yellow to red with the increase in the jam length), the driver can intuitively obtain jam information passively, without receiving the jam information actively via radio or the like, in a real time.
In another possible configuration, the laser beam 13 may be high-speed modulated by the modulation unit 144 and sent to the automobile 102 to transmit running information. In this case, by providing the automobile 102 with an optical receiver (signal receiver) 145 that receives the modulated laser beam 13, it is possible to receive the modulated laser beam 13 and use the running information converted into electric signals.
With the above-described configuration, the laser beam 13 can be irradiated with good directivity along the road surface 101 and the driver can be alerted with good visibility. At the same time, various types of information using the laser bean 13 as a carrier can be transmitted as modulated signals and received by the receiver 145 installed on the automobile 102. As a result, information relating to the road in the area where the automobile 102 is located, such as traffic information, can be received in a real time mode and therefore convenience for the driver can be improved.
Further, in the present embodiment, running information and traffic information are explained as examples of the transmitted and received information, but the information that is the object of transmission and reception in the present embodiment is not limited to the aforementioned types of information and may include meteorological information and guidance information for neighboring areas. Further, the medium receiving the information is not limited to automobiles and it goes without saying that the above-described configuration is applicable to the case in which a person receives guidance information via a portable terminal or the like.
Further, as shown in
In this case, the external light irradiating the road surface 101 or the central separation zone 143 is detected by the optical sensor 146. The external light detected by the optical sensor 146 is converted into an electric signal and sent to the control unit 145. The control unit 145 adjusts and controls the intensity of the laser beam 13 on the basis of the inputted electric signal. The control unit 145 thus adjusts and controls the intensity or color of the laser beam 13, for example, correspondingly to the surrounding lightness. As a result, the laser beam 13 that can be optimally recognized by the driver can be irradiated at a necessary and sufficient power level. Therefore, power consumption can be reduced.
The present linear guiding portion 141 is preferably provided with an infrared radiation sensor 148 as a human body detection sensor that detects the presence of a pedestrian (person) 147.
In the configuration provided with an infrared radiation sensor as a human body detection sensor, where a person 147 approaches an infrared radiation sensor 148, the quantity of infrared radiation 147a in the vicinity of the sensor 148 increases. As a result, the infrared radiation sensor 148 can detect the presence of the person 147 by detecting the increase in the quantity of the infrared radiation 147a. When such a configuration is applied, for example, to a road or a parking area, where the person 147 enters the area close to an automobile (mobile body) 102, the presence of the person is immediately detected and the driver is notified thereof. In addition, the guiding device 140 with increased safety can be realized. The human body detection sensor is not limited to the infrared radiation sensor 148 and, for example, a pyroelectric infrared radiation sensor may be used.
In the present embodiment, similarly to the above-described embodiments, a configuration may be used in which the laser light source 14 includes an RGB beam source composed at least of an R beam source 14R emitting an R beam 13R, a G beam source 14G emitting an G beam 13G, and a B beam source 14B emitting an B beam 13B. With such a configuration, the laser beam 13 of deep color that excels in color reproducibility can be irradiated. As a result, the visibility of the guiding device can be further improved.
Similarly to the above-described embodiments, in the laser light source of the present embodiment, the liner guiding portion may be constituted by a propagation portion A in which the laser beam 13 from the laser light source 14 propagates with low loss and an irradiation portion B that irradiates the laser beam 13 with good directivity by scattering. With such a configuration, the laser beams 13, 54 can be used with good efficiency and therefore, the laser light source 14 can be operated at a low level of power consumption.
Similarly to the above-described embodiments, the laser light source of the present embodiment may be a beam source including no RGB beam source. In this case, it is preferred that the laser light source 14 include at least the G beam source 14G. A high-output SHG laser excited by a semiconductor laser and outputting the G beam 13G with a wavelength close to 535 nm is preferably used as the G beam source 14G. In this case, the green laser beam 13 with high visibility to human eyes can be used. Therefore, a linear guiding portion with high visibility can be provided at a low level of power consumption.
The green laser beam 13 features a high photoelectric conversion efficiency and a narrow half-width of wavelength spectrum. Therefore, for example, in comparison with the case in which the same effect is obtained by using light from a green LED, the green laser beam 13 makes it possible to realize a high visibility at about one tenth of the power.
A guiding device of yet another embodiment of the present invention will be explained below with reference to
As shown in
In the present embodiment, the laser light source 14 is controlled in a fireproof shelter (not shown in the figure) in a separate room and the light is guided by a fiber.
In the case of fire, hazardous fumes and gases (carbon dioxide and the like) are accumulated close to the ceiling, and therefore when escaping to the outside of the building, people are usually assumed to crawl out close to the path surface of the passage 154.
Accordingly, in the present embodiment, the linear guiding portion 151 is installed in a lower half of the side surface 153 constituting the internal passage at a height equal to or less than half of the height H. As a result, the passage can be made clearly visible, for example, to people who try to escape the fire by crawling out. As a result, the people can be guided so as to escape rapidly to the outside. Therefore, the possibility of emergency escape is increased. Thus, the guiding device 150 of the present embodiment can be advantageously used as a guidance lamp of the indoor passage.
It is preferred that glass such as quartz glass be used as a material for the linear guiding portion 151.
In this case, since glass excels in heat resistance and can withstand a high temperature of equal to or higher than 1000° C., where the laser light source 14 is placed in a heat-resistant shelter in a separate room, as described hereinabove, the passage can be indicated without trouble even in the case of fire. Therefore, the laser light source can be advantageously used as an emergency guidance lamp.
Further, since the fiber itself is extremely thin and takes absolutely no place, the fiber does not narrow the evacuation passage.
A configuration with full color illumination such as shown in
The linear guiding portion 151 in the present configuration may be also installed on a road surface 154 of the passage, rather than on the side surface 153.
The diffusing material 15d or diffusing material 35 described in the embodiments hereinabove may be a transparent substance with a refractive index different from that of the substance surrounding the diffusing material, or a fluorescent material may be used instead of the diffusing material 15d or diffusing material 35. The fluorescent material is not limited to the substance described in Embodiment 2, provided that the light of desired color is emitted.
The guiding device of yet another embodiment of the present embodiment will be described below with reference to
In
Part of the laser beam 13 falling at an angle α to the normal to the end surface of the unit-length fiber 161a is irradiated at an angle α to the normal to the end surface. The remaining incoming laser beam 13 is transmitted via the end surface at an angle β obeying the Snell's law and enters the end surface of the unit-length fiber 161b. Likewise, part of the laser beam 13 falling at an angle β on the end surface of the unit-length fiber 161b is transmitted at an angle α to the normal to the end surface. The remaining part of the incident laser beam 13 is reflected at an angle β, reaches the end surface of the unit-length fiber 161a, and part of the beam is further transmitted at an angle α inside the unit-length fiber 161a. Similar reflection is thereafter repeated between the end surfaces of the unit-length fibers 161a and 161b. All of the laser beams that underwent such multiple reflections at the end surfaces of the unit-length fibers 161a and 161b are irradiated as the laser beams 13b in the direction at the same angle γ. More specifically, for example, the fibers (refractive index=1.5) cut at an angle θ=45° are joined by the joining member 164 (refractive index 1.7), and the laser beam falling horizontally (that is, α=45°) is irradiated directly upward from the fiber (that is, γ=0°). In this case, the laser beam 13b taken to the outside of the fiber constitutes about 0.8% of the incoming laser beam 13.
The linear guiding portion of the present embodiment can take out the laser beam from each joining portion. Therefore, light-emitting portions can be readily provided with a predetermine spacing (that is, for each length of the unit-length fiber). Further, with the configuration shown in
It goes without saying that the above-described configuration is not limited to one example, and the angle θ of the end surfaces, angle α of incidence, and refractive index can be appropriately selected. Further, the refractive index of the joining member 164 may be made zero (that is, the gap between the unit-length fibers is not filled).
The unit length of the fibers is preferably, for example, 1 m. In this case, equidistant regular irradiation is possible and power consumption can be reduced, while conducting effective irradiation. Further, since the operations of cutting the fibers and processing the end surfaces can be conducted for large quantities in advance at a plant, inexpensive guide can be provided. The unit length is merely an example, and it goes without saying that the fiber length can be changed to any length as required by the installation site.
The guiding device 160 may also have a configuration shown in
In the configuration shown in
In the above-described embodiments, quartz and resin are considered as materials constituting the fiber core and cladding, but it goes without saying that the materials can be freely selected according to the environment in which the fibers will be used, length, and application. When the fibers are to be simply used outdoors for a long time, the use of quartz fibers that excel in endurance can be considered, and when curved fibers are installed, the use of resin fibers such as acrylic or polycarbonate fibers that excel in flexibility even when they have a large thickness can be considered, but these fibers are not limiting and appropriate fibers such as fluoropolymer resin, deuterated polymer, or polystyrene fibers can be freely selected. A combination of quartz as a core and a resin as a cladding may be also used.
As described above, the guiding device that guides a mobile body by light according to one aspect of the present invention includes a laser light source that emits a laser beam, and a linear guiding portion that propagates the laser beam and is extended in a guiding direction on a road surface on which the mobile body travels, wherein the linear guiding portion irradiates the laser beam with directivity in the guiding direction from a surface where the linear guiding portion extends, while propagating the laser beam.
With such a configuration, the laser beam emitted from the laser light source is irradiated with directivity in the guiding direction from an extension surface thereof, while propagating the laser beam in the linear guiding portion extended on the road surface. Thus, the linear guiding portion has both the function of propagating the laser beam emitted from the laser light source and the function of irradiating and guiding the laser beam from the extension surface. The linear guiding portion of such a configuration is significantly different from a typical optical fiber as described below.
Thus, a typical optical fiber has only a function of propagating the light, and in the typical optical fiber, the propagating light is irradiated only from the distal end of the optical fiber. Therefore, where a device for guiding by light is to be realized by using typical optical fibers, a large number of optical fibers should be used and distal ends of the large number of optical fibers should be arranged as shown in Patent Document 2.
By contrast, as described above, the linear guiding portion of the present guiding device takes out and irradiates the laser beam from the extension surface, while propagating the laser beam. Therefore, the desired laser beam can be taken out over a wide range from the extension surface of one linear guiding portion. Thus, with the present guiding device, guiding by light can be realized easily and over a wide range by extending the linear guiding portion connected to the laser light source. As a result, it is possible to realize a low-cost guiding device that is simple in structure and installation and easy to maintain. Further, the present guiding device irradiates a laser beam with good directivity along the guiding direction. Therefore, the laser beam is easily seen, for example, by a driver of a mobile body and excels in visibility.
The laser light source is preferably installed at the road surface or below the road surface.
Although the laser beam device is disposed outside the road surface or below the road surface, as described hereinabove, guiding by light can be easily realized over a wide range by extending the linear guiding portion. Therefore, the laser light source can be provided, for example, inside a room of an administrative building outside the road surface or in a protective chamber below the road surface, and the laser light source can be easily and adequately protected from water, atmosphere, and sunlight. As a result, the service life of the entire guiding device can be extended.
It is preferred that the linear guiding portion include a fiber having a core and a cladding, and at least one of the core and the cladding include a diffusing material.
By using the fiber including a diffusing material in at least either of the core and the cladding, it is possible to realize easily a linear guiding portion. Further, by adequately designing the arrangement or density of the diffusing material inside the fiber in such a configuration, it is possible to irradiate the desired laser beam easily and with good directivity.
The linear guiding portion is preferably provided with a plurality of mirrors or prisms that cause the laser beam to exit from the surface, where the linear guiding portion extends, to the outside.
By so using a plurality of mirrors or prisms, it is possible to irradiate the laser beam easily and with good directivity in the desired direction.
It is preferred that the above-described configuration further include a light-guiding plate that is connected to a distal end portion of the linear guiding portion and irradiates the laser beam as a plane-like beam.
In this case, the laser beam can be irradiated as a plane-like beam and therefore the laser beam can be irradiated with a certain width on the road surface. As a result, visibility can be further increased.
The linear guiding portion preferably includes a propagation line in which the laser beam propagates, and a contact portion that is provided to be capable of coming into contact with a surface of the propagation line on an exit side of the laser beam and takes out part of the laser beam from the propagation line to the outside.
With such a configuration, by adequately designing the arrangement of the contact portion that is brought into contact with the propagation line, it is possible to take the laser beam out with good efficiency in a desired position. For example, the laser beam can be taken out periodically.
The linear guiding portion is preferably folded back along the road surface to obtain a parallel arrangement.
In the linear guiding portion, the quantity of laser beam exiting from the extension surface of the linear guiding portion decreases with the distance from the laser light source, but in the linear guiding portion that is folded back to obtain a parallel arrangement, the portion that is close to the laser light source and the portion that is far from the laser light source are parallel to each other and stacked, thereby making it possible to obtain an almost uniform irradiation intensity of the laser beam from each position along the road surface and increase visibility.
The linear guiding portion is preferably disposed on a top portion of a side surface of a convex central separation zone provided on the road surface.
In this case, the guiding device can be disposed in a compact manner in a location with good visibility.
The linear guiding portion is preferably disposed in a lower-half region of a side surface constituting an indoor passage as the road surface.
In this case, a guiding device suitable as a guidance lamp for indoor passages can be realized.
The linear guiding portion preferably includes a plurality of branch fibers arranged to irradiate the laser beam as a plane-like beam.
As a result, plane-like irradiation of a laser beam can be realized with a simple configuration and visibility can be further increased.
It is preferred that a mirror be disposed around the linear guiding portion and the laser beam exiting the linear guiding portion be reflected by the mirror.
The mirror is preferably a paraboloidal mirror.
It is preferred that the linear guiding portion include a fiber in which the laser beam propagates, and the fiber be curved in a position in which the laser beam is taken out.
The curving diameter of the fiber in the position in which the laser beam is taken out preferably decreases towards the downstream side of the fiber.
As a result, the total reflection condition is easily exceeded inside the fiber at the downstream side thereof and a laser beam can be irradiated with a uniform quantity of light, regardless of the distance from the laser light source.
It is preferred that the linear guiding portion include a fiber in which the laser beam propagates, the fiber have a cladding and a hollow portion surrounded by the cladding, and a transparent liquid including a fluorescent material or a diffusing material be injected into the hollow portion.
In such a configuration, it is preferred that a plurality of transparent liquids that are not mutually miscible be injected into the hollow portion.
The linear guiding portion preferably includes a taper fiber in which a cross section diameter changes with the distance from the laser light source.
The linear guiding portion preferably has an annular structure such that an end portion thereof is in contact with a laser beam entry portion.
The linear guiding portion is preferably a taper fiber in which a cross section diameter changes with the distance from the laser light source.
The linear guiding portion preferably includes a fiber having a core and a cladding, and a refractive index of the core is lower than a refractive index of the cladding.
In this case, a laser beam can be easily taken out over a long region with a uniform distribution.
The linear guiding portion is preferably formed by joining a plurality of fibers having a predetermined length, and the laser beam is taken out from the joining portions in which the plurality of fibers are joined.
In this case, the laser beam can be taken out from the joining portions. Therefore, light-emitting portions can be easily provided for each predetermined distance. Further, since the laser beam can be taken with good directivity to the outside of the fiber, a configuration with excellent visibility can be obtained.
The above-described configuration preferably further includes a fixing portion that fixes the joining portion according to a predetermined orientation with respect to the road surface.
The guiding device according to another aspect of the present invention includes: a laser light source that emits a laser beam; a fiber that guides the laser beam entering thereto; and a light-guiding sheet that irradiates the laser beam guided by the fiber as a two-dimensional beam, and the light-guiding sheet is processed into a mesh-like shape.
With such a configuration, since a light-guiding sheet is used that has been processed into a mesh-like shape, even if part of the propagation path is cut, the laser beam from other locations bypasses the cut portion and therefore the laser beam can be caused to exit the propagation path downstream of the cutting position. As a result, a highly reliable guiding device of a simple configuration from which the laser beam exits with good directivity over a wide range can be realized.
It is preferred that the above-described configuration further include a control unit that controls the laser light source and changes an emission frequency or color of the laser beam, wherein the control unit provides information to a driver of the mobile body by modulating the emission frequency of the laser beam within a range from 0.2 Hz to 10 Hz or by changing the color of the laser beam.
In this case, in addition to the guiding function, it is possible to alert the driver by providing viewable information such as traffic information.
It is preferred that the above-described configuration further include a modulation unit that modulates the laser beam, the modulation unit modulating the laser beam as a carrier and transmitting information to the mobile body.
With the above-described configuration, it is possible to use the laser beam as a carrier, carry various kinds of information as modulation signals thereupon, and send the modulated laser beam to the mobile body. As a result, where the laser beam is received by a receiver installed at the mobile body, information relating to the road in the area where the mobile body is located, such as traffic information, can be received in a real time mode. Therefore, convenience for the driver can be improved.
It is preferred that the above-described configuration further include an optical sensor that detects a lightness of the road surface, and a control unit that controls the laser light source on the basis of a detection result of the optical sensor.
In this case, by changing the intensity or color of the laser beam in response to the ambient lightness, it is possible to irradiate, with sufficient and necessary power, the layer beam that can be optimally viewed by the driver.
It is preferred that the linear guiding portion in the above-described configuration further include a human body detection sensor that detects the presence of a pedestrian, and a control unit that controls the laser light source on the basis of a detection result of the human body detection sensor.
In this case, a person present close to the mobile body, for example in a parking lot, can be immediately detected and the driver can be notified thereof, thereby making it possible to realize a guiding device with even higher safety.
Industrial Applicability
The guiding device in accordance with the present invention uses fiber configuration and arrangement on a road surface and ensures directivity of laser beam take-out from the fiber by optical means. As a result, the guiding device can be advantageously used in a road display device that is simple in structure and installation and easy to maintain and excels in visibility.
Further, by using the speckle noise or color of laser beams, it is possible to increase visibility at a necessary and sufficient power. As a result, operation with low power consumption is enabled, a large volume of information can be provided to the mobile body driver in a real time mode, and the mobile body can be conveniently operated.
Specific embodiments and examples presented in the detailed description of the invention merely serve to clarify the technical contents of the invention and are not to be considered in a limiting sense. Thus, the present invention can be practiced with various modifications within the spirit of the invention and scope of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2008-172976 | Jul 2008 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2009/003022 | 6/30/2009 | WO | 00 | 1/10/2011 |
